The present invention comprises a new non-dwarfing rootstock for pears (Pyrus communis) designated xe2x80x98BU/233xe2x80x99 for experimental purposes and now referred to by the varietal name xe2x80x98Rhenus 3xe2x80x99.
The new variety was selected by me in a cultivated area in a orchard at the Research Station of Viticulture and Horticulture in Geisenheim, Germany. Pear varieties xe2x80x98Old Homexe2x80x99 (female) (unpatented, believed to be publicly available) and xe2x80x98Bonne Louise d""Avranchesxe2x80x99 (male) (unpatented, believed to be publicly available) were cross-pollinated and a substantial number of the resulting seeds were germinated. A number of seedlings were then used as rootstocks for pear varieties grafted onto the rootstocks. The grafted seedlings including xe2x80x98Rhenus 3xe2x80x99 were then evaluated as rootstocks. xe2x80x98Rhenus 3xe2x80x99 was then selected for further testing.
xe2x80x98Rhenus 3xe2x80x99 has not been observed under all possible environmental conditions and its phenotype may vary significantly with variations in environment such as temperature, light intensity, and day length, without any variation in genotype. However, the following unique combination of characteristics relating to the use of xe2x80x98Rhenus 3xe2x80x99 as a rootstock for pear varieties, distinguish xe2x80x98Rhenus 3xe2x80x99 from all other pear varieties of which I am aware: (1) causes non-dwarfing of pear varieties; (2) compatible as a rootstock with all pear varieties tested; (3) high yield efficiency; (4) early yield (precocity); (5) substantially uniform fruit size; (6) high frost hardiness; (7) no suckering; (8) good soil adaptation; and (9) easy propagation from hardwood and softwood cuttings. These characteristics are established and transmitted through succeeding asexual propagations.
Asexual reproduction of xe2x80x98Rhenus 3xe2x80x99 is accomplished, for example, by tissue culture; softwood and hardwood cuttings, e.g., using 2,000 ppm indole-3-butyric acid (IBA) (quick dipping) by the xe2x80x9cmethode Trefoisexe2x80x9d (R. Trefoise, xe2x80x9cDescription des techniques de bouturage feuille des nouveaux sujets porte-greffe nanifiants dur cerisier,xe2x80x9d Note technique du Centre de Recherches Agronomiquies de l""Etat Gembloux, No. 10/50, Septembre 1988, I.S.S.N. 0771-0607, 1988).